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216
Lin et al. – New Scleractinian Coral From Taiwan
USA) instrument.
Skeleton vouchers were deposited at the
National Museum of Natural Science (NMNS),
Taichung, Taiwan and at the Museum of Tropical
Queensland (MTQ), Townsville, Australia. In
the morphological description, the following
abbreviations were used: CD, calicular diameter;
GCD, great CD; Sx, septa of the x order; Px, pali
of the x order; and H, height. Tissue samples
preserved in CHAOS solution (Fukami 2004) were
used for DNA extraction.
Symbiodinium identification
Following LaJeunesse (2002), denaturing
gradient gel electrophoresis (DGGE) of the internal
transcribed spacer (ITS)-2 region was performed
to identify the Symbiodinium clade present in P.
chaishanensis sp. nov. The ITS-2 region was
amplified using primers ITS2 clamp and ITSintfor
2 developed by LaJeunesse and Trench (2000). A
polymerase chain reaction (PCR) was performed
with a touch-down cycle according to LaJeunesse
(2002). PCR products were subjected to electrophoresis
for 15-16 h on denaturing gradient gels
(45%-80%) using a CBS Scientific System (Del
Mar, CA, USA). Gels were stained with SYBR
green (Molecular Probes, Eugene, OR, USA) for
20 min, and photographed for further analysis.
Bands were excised from the gel and sent for
direct sequencing. Resulting sequences were
deposited in the NCBI database (with accession
nos.: 180016-180021)
Sequence analysis and phylogeny
Forty mt16S rDNA and the cytochrome c
oxidase subunit I (COI) sequences, including
these 2 regions from the complete mt genome of
P. chaishanensis sp. nov (Lin et al. 2011), were
retrieved from GenBank. This dataset contained
11 robust and 4 complex scleractinian families.
Phylogenetic analyses were performed using
MEGA 4.0 (Tamura et al. 2007) for Neighborjoining
(NJ) and MrBayes 3.1.2 (Huelsenbeck
and Ronquist 2001) for Bayesian inference (BI).
The most appropriate model of nucleotides was
determined to be HKY+I using MrModeltest vers.
2.3 (Nylander 2004). The NJ analyses were
performed with 500 replicates, and for the BI, 2
runs each of 10 6 generations were calculated
for each marker with topologies saved every
100 generations. The 1st quarter of the saved
topologies were discarded as burn-in, and the
remaining ones were used to calculate posterior
probabilities.
Systematic description
RESULTS
Subclass Hexacorallia.
Order Scleractinia Bourne, 1900.
Suborder Caryophylliina Vaughan & Wells, 1943.
Family Caryophylliidae Dana, 1846.
Genus Polycyathus Duncan, 1876.
Polycyathus chaishanensis sp. nov.
Illustrations of the holotype are given in figures 3C, D, 4A-C;
and illustrations of the paratype are given in figure 4D, E.
Materials examined: Holotype: NMNS-6309-
001 (Taichung, Taiwan). Paratypes: NMNS-6309-
002, NMNS-6309-003 (Taichung, Taiwan), and
MTQ G64703 (Queensland, Australia, 1 specimen).
Type locality: 22°38'18''N, 120°15'19''E (Taiwan),
3 m in depth.
Description: Small reptoid colonies formed by
closely spaced cylindrical corallites arising from a
common coenosteum or from stolons. Holotypic
colony consisting of approximately 70 corallites.
Extratentacular budding common; however, some
corallites displaying intratentacular division. Calice
circular to slightly elliptical. Largest corallite
examined 3.65 × 3.73 mm in CD and 4.0 mm in
H. Theca thick. Costae more prominent near
calicular edge. All costae equal in width (about
0.21 mm wide), slightly convex, and bearing low,
coarse granules. Intercostal striae deep and
flat near calicular edge, becoming less distinct
in direction of base. Coenosteum and theca
white, but columellar elements usually light-brown
pigmented. Vivid-red to dark brown sub-pellucid
polyps considerably expanded above calicular
edge; tentacles long, slender, with knobby end,
and covered by small white verruca.
Septa hexamerally arranged in 4 incomplete
cycles, according to formula: S1 ≥ S2 > S3 > S4.
Corallites < 2 mm in GCD with 12 or fewer septa,
but larger corallites (up to 3.7 mm in GCD) with
several pairs of S4 totaling up to 34 septa. S1
exsert (0.5-0.7 mm), with straight and almostvertical
axial edges sometimes bearing small,
cylindrical (0.24 mm in diameter) palus. S2 only
slightly less exsert and equal or narrower than
S1. S3 less exsert, thinner, and about 2/3 width
of S2. Axial edges of S1-S2 dentate, those of S3
laciniated. S4 1/2-2/3 width of S3. Well-developed
P3 (sometimes bilobated) present before S3. If